package com.atguigu.gulimall.product.service.impl;

import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;
import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import org.springframework.stereotype.Service;


/**
 * @author lupen
 */
@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements
    CategoryService {

  @Override
  public PageUtils queryPage(Map<String, Object> params) {
    IPage<CategoryEntity> page = this.page(
        new Query<CategoryEntity>().getPage(params),
        new QueryWrapper<CategoryEntity>()
    );

    return new PageUtils(page);
  }

  @Override
  public List<CategoryEntity> listWithTree() {
    //1、查出所有分类
    List<CategoryEntity> categoryEntities = baseMapper.selectList(null);
    //2、组装成父子的树形结构
    List<CategoryEntity> level1Menus = categoryEntities.stream()
        .filter(categoryEntity -> categoryEntity.getParentCid() == 0).map((menu) -> {
          menu.setChildren(getChildrens(menu, categoryEntities));
          return menu;
        }).sorted(Comparator.comparingInt(menu -> (menu.getSort() == null ? 0 : menu.getSort())))
        .collect(Collectors.toList());

    return level1Menus;
  }

  @Override
  public void removeMenusByIds(List<Long> asList) {
    //TODO 1、检查当前删除的菜单是否被别的地方引用

    baseMapper.deleteBatchIds(asList);
  }

  private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all) {
    List<CategoryEntity> children = all.stream()
        .filter(categoryEntity -> categoryEntity.getParentCid().equals(root.getCatId()))
        .map(categoryEntity -> {
          categoryEntity.setChildren(getChildrens(categoryEntity, all));
          return categoryEntity;
        }).sorted(Comparator.comparingInt(menu -> (menu.getSort() == null ? 0 : menu.getSort())))
        .collect(Collectors.toList());
    return children;
  }
}